just how much performance gain overlap is there between games?

[alexman]

to some degree all the pdx games use clauswitz and i assume all tech leads talk in studio between eachother.
whenever they realize a way to improve tickspeed how fast is this ported to other games?
how fast could u roll out dx12 or vulkan to other games.
do u have inhouse training courses on how to write neat code to avoid bottlenecks?

 

[SolSys]

(Not a PDX answer, so may not be fully correct.)

While all games are based on the Clausewitz engine, they were forked at different points in time and thus different versions.

This makes it a bit hard to backport features from newer games to much older ones (for example, from V3 to EU4).

This is alleviated to an extent in the more newer engine revisions as it became more modular in nature -- rendering is self-contained, same for multiplayer backend, strategic AI, and so on.